摘要
一、前言 地开石是一种比较少见的粘土矿物,是含水的层状铝硅酸盐。它与高岭石相同,属于1:1型高岭石族二八面体。但层的堆叠方式不同,各层的位移是1/6a_(0) 1/2b_(0)[1]。在扫描电镜下地开石晶体一般比高岭石厚大,堆叠成塔形,即呈假六方板状晶体,一端较小。
Dickite is a relatively uncommon clay mineral, belonging to the kaolin group and having dioctahedral structure. It occurs along the cracks and sliding planes at false roof and top of the coal bed (Permian Shanxi Formation) in Fengying mining area, Jiaozuo coal basin, and is 1-10mm (generally 5mm) in thickness. It is usually white or greyish white in colour, and grows grey when subjected to carbon contamination. The differential thermal analysis indicates that the endothermic valleys appear at temperatures higher than 60013, that a comparatively intense exothermic peak occurs at 9801, and that the mineral has considerably high degree of order. Absorption peaks are observed on the infrared spectrum curve from 3700 CM^(-1) to 3600 CM^(-1) with the character of gradual intensification. The six diffraction peaks at 26 values from 20° to 24° and the double peak at 20 values from 35° to 40° on the x-diffraction pattern also denote the mineral of dickite. The electron microscope analysis demonstrates that this mineral assumes the shape of accumulated tower, and the chemical analysis shows that its components are mainly SiO_(2) and A1_(2)O_(3) with some absorbed water——other constituents are rarely observed. This further confirms that this mineral is undoubtedly dickite with pure chemical components. All these data will contribute to the genetic study of this mineral.
出处
《岩矿测试》
CAS
1985年第1期30-38,I0006,共10页
Rock and Mineral Analysis
